<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>body宽高相对屏幕100%自适应</title>
    <style >
        html,body {
            height: 100%;
        }
        body {
            background: #e1e1e1;
        }
        .app {
            height: 100%;
            background: #789267;
        }
    </style>
</head>
<body>
    <div class="app"></div>
</body>
</html>
